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Electrostatographic apparatus having improved transport memberRelated Patent Categories: Electrophotography, Document Handling, Copy, Delivering From Transfer Position, To Fixing (e.g., Fuser)Electrostatographic apparatus having improved transport member description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20070196151, Electrostatographic apparatus having improved transport member. Brief Patent Description - Full Patent Description - Patent Application Claims
FIELD OF THE INVENTION [0001] The present invention relates to electrostatographic image reproduction and, more particularly, to an electrostatographic apparatus that includes a transport web provided with a release oil-absorbing layer. BACKGROUND OF THE INVENTION [0002] Electrostatographic printers produce images by transferring polymeric toner particles from a photoreceptor to a receiver and fixing the toner particles to the receiver with heat and pressure. Various additives and oils are used to aid the transfer of the particles. Silicone oil is commonly used as a release oil because it is thermally stable and incompatible with the toner particles and other polymers in the printer; unfortunately, however, it tends to spread throughout the machine as prints are made. Release oil spread is exacerbated by duplex printing, which entails the application of images to both sides of a receiver sheet. Oil provided to the receiver during application of the first image on one side of a receiver is carried into the printer on the paper transport web in the course of applying the second image to the opposite side, leading to objectionable image artifacts such as non-uniform density and differences in gloss. Details of fuser oil application are given in U.S. Pat. Nos. 5,157,445 and 5,512,409, the disclosures of which are incorporated herein by reference. [0003] Ink-jet printers produce images by ejecting droplets of ink onto receivers that absorb ink. Porous coatings of inorganic particles on the receivers improve the image quality by, for example, causing more rapid drying of the ink, reducing image spread, and producing more uniform ink coverage. Silica and alumina particles incorporated into binder polymers are used for coatings on paper and coatings on clear plastics such as polyethylene terephthalate sheets. While larger particles can be used to produce opaque coatings on paper substrates, smaller particles are required for coatings that are transparent in a binder, which is also desirably transparent and colorless. Microporous ink-jet recording elements prepared using psuedo-boehmite in organic polymer matrices are described in, for example, U.S. Pat. Nos. 5,723,211; 5,605,750; 5,085,698; 4,879,166; and 4,780,356, the disclosures of which are incorporated herein by reference. [0004] Similar materials have also been used in electrophotography. U.S. Pat. Nos. 5,406,364 to Maeyama et al. assigned to Canon Kabushiki Kaisha. A cleaner in the form of a web is prepared by immersing a piece of non-woven fabric into a colloidal solution of alumina or silica sol. Poly(vinyl alcohol) may also be added. The patent teaches that porous particles can absorb release agent to clean contaminated surfaces in an electrophotographic apparatus. There is no mention of transparency, nor reference to the size of the oxide particles. The web is used to remove silicone oil from the transfer drum. The coating subjected to repeated charging and discharging in the electrophotographic process thus it does not have to possess insulating properties. Furthermore the material itself is not cleaned of toner from the electrophotographic process and, therefore, does not have to possess a low surface energy. [0005] U.S. Pat. No. 5,903,802 to Watanabe also of Cannon uses pseudo-boehmite particles as well as silica particles, porous ceramics and foamed metals to clean transfer members and photoreceptors. Release agent absorbing layers are placed in various parts of the electrophotographic apparatus such as the feed passage member. Particle size is not important because there is no requirement for the layer to be transparent, nor is the coating subjected to repeated charging and discharging in the electrophotographic process. Furthermore the material itself is not cleaned of toner from the electrophotographic process and therefore does not have to possess a low surface energy. [0006] Pseudo-boehmite coatings have also been applied to the photoreceptors used in electrophotographic printing. U.S. Pat. No. 5,693,442, the disclosure of which is incorporated herein by reference, describes the incorporation of a nickel metallized dye into an overcoat of pseudo-boehmite to act as a filter to protect the light sensitive element. The inorganic particles and 5 wt. % of the metallized dye in a poly(vinylpyrrolidone) binder form a transparent layer that can be charged under a corona charger and discharged by exposure to actinide radiation. [0007] The mitigation of objectionable image artifacts such as non-uniform density and differences in gloss that result from the spread of release oil from an imaged receiver into the reproduction apparatus, particularly during a duplex printing process, is provided by the present invention. SUMMARY OF THE INVENTION [0008] The present invention is an electrostatographic reproduction apparatus which includes a primary imaging member for producing an electrostatic latent image on a receiver, a development station for applying toner particles to said latent image which forms a developed toner image on the receiver. A fuser assembly is included for fixing the developed toner image, to form a fused toner image on the receiver. A transport member is provided for transporting the receiver to or from the fuser assembly, the transport member having a substrate bearing an oil-absorbing layer that includes transparent aluminum inorganic particles of pseudo-boehmite, dispersed in an organic binder, and a wax having a melting point less the 100.degree. C. BRIEF DESCRIPTION OF THE DRAWINGS [0009] FIG. 1 is a schematic side elevational view of an electrostatographic reproduction apparatus that includes an endless web transport member for moving a receiver to and from a fuser assembly; [0010] FIG. 2 is a plot of release oil on a transport web versus the number of duplexed contacts obtained using a standard PET web; and [0011] FIG. 3 is a plot of release oil on a transport web versus the number of duplexed contacts obtained using a web containing an oil-absorbent coating in accordance with the present invention. DETAILED DESCRIPTION OF THE INVENTION [0012] FIG. 1 shows an exemplary image-forming electrostatographic reproduction apparatus, designated generally by the numeral 10, that includes a primary image-forming member, for example, a drum 12 having a photoconductive surface, upon which a pigmented marking particle image, or a series of different color marking particle images, is formed. To form images, the outer surface of drum 12 is uniformly charged by a primary charger such as a corona charging device 14, and the uniformly charged surface is exposed by suitable exposure device such as a laser 15 to selectively alter the charge on the surface of the drum 12, thereby creating an electrostatic image corresponding to an image to be reproduced. The electrostatic image is developed by application of pigmented marking particles to the image bearing photoconductive drum 12 by a development station 16 that may include from one to four (or more) separate developing devices. [0013] The marking particle image is transferred (or multiple marking particle images are transferred one after another in registration) to the outer surface of a secondary or intermediate image transfer member, for example, an intermediate transfer drum 20 that includes a metallic conductive core 22 and a compliant layer 24 that has relatively low resistivity. With such a relatively conductive intermediate image transfer member drum 20, transfer of the single color marking particle images to the surface of drum 20 can be accomplished with a relatively narrow nip 26 and a relatively modest potential applied by potential source 28. [0014] A single marking particle image, or a multicolor image comprising multiple marking particle images respectively formed on the surface of the intermediate image transfer member drum 20, is transferred in a single step to a receiver S, which is fed into a nip 30 between intermediate image transfer member drum 20 and a transfer backing member 32. The receiver S is fed from a suitable receiver member supply (not shown) into nip 30, where it receives the marking particle image. Receiver S, exits nip 30 and is transported by a transport web 54 to a fuser assembly 56, where the marking particle image is fixed to receiver S by application of heat and/or pressure. Receiver member S bearing the fused image is transported by transport web 54 to a storage location (not shown) or is inverted by a mechanism (not shown) for transfer of a second image to the reverse side of receiver S. [0015] A transfer-backing member 32 that includes an endless support 34 is entrained about a plurality of support members, for example rollers 40, 42, 44, and 46. Support roller 42 is electrically biased by potential source 33b to a level sufficient to efficiently urge transfer of marking particle images from intermediate image transfer member drum 20 to receiver member S. At the same time, support roller 40 is electrically biased, for example to ground potential, or electrically connected to source 28 or a separate potential source 33a, to a level sufficient to eliminate ionization and premature transfer upstream of nip 30. [0016] Appropriate sensors (not shown) of any well known type are utilized in reproduction apparatus 10 to provide control signals for apparatus 10, which are fed as input information to a logic and control unit L that produces signals for controlling the timing operation of the various electrographic process stations. [0017] To facilitate release of the fixed toner image from fuser assembly 56, a release agent such as silicone oil is applied to imaged receiver S by a mechanism such as depicted in FIG. 1 of the previously cited U.S. Pat. No. 5,157,445. As already noted, an excess of this oil can be carried to other parts of apparatus 10, especially in the course of duplex printing, resulting in objectionable image artifacts. [0018] In accordance with the present invention, a transport member in an electrostatographic reproduction apparatus 10, depicted in FIG. 1, includes a release oil-absorbing layer disposed on a substrate. Although the transport member is exemplified as a continuous web 54 in FIG. 1, it may take other forms such as, for example, a drum or roller. Apparatus 10 further includes a primary image-forming member, which is exemplified in FIG. 1 as a drum 12 but may be constructed in another form such as, for example, a roller or a belt. The reproduction apparatus optionally includes, operationally associated with the primary image-forming member, an intermediate image transfer member, which is depicted in FIG. 1 as a drum 20 but may also be constructed in another form such as, for example, a roller or a belt. [0019] A transport member provided with an oil-absorbing layer in accordance with the present invention may be included in a full color reproduction apparatus having four toner development stations for cyan, magenta, yellow, and black, as depicted in FIG. 8 of U.S. Pat. No. 6,075,965, the disclosure of which is incorporated herein by reference. A developed multicolor image, following fixing by a fuser assembly, can be transported to a storage site or circulated back for recording an image on the opposite side of the receiver, as described in U.S. Pat. No. 6,184,911, the disclosure of which is incorporated herein by reference. Continue reading about Electrostatographic apparatus having improved transport member... Full patent description for Electrostatographic apparatus having improved transport member Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Electrostatographic apparatus having improved transport member patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Electrostatographic apparatus having improved transport member or other areas of interest. ### Previous Patent Application: Media storage apparatus and image forming apparatus Next Patent Application: Sheet feeding apparatus and image forming apparatus Industry Class: Electrophotography ### FreshPatents.com Support Thank you for viewing the Electrostatographic apparatus having improved transport member patent info. 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